Multi-speed transmission

ABSTRACT

A transmission is provided having an input member, an output member, at least three planetary gear sets, a plurality of interconnecting members and six torque transmitting mechanisms. The torque transmitting mechanisms include clutches and brakes that are actuatable in combinations of three to establish at least ten forward gear ratios and at least one reverse gear ratio.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/640,798 filed Mar. 6, 2015 which claims the benefit of U.S.Provisional Application No. 61/968,156 filed Mar. 20, 2014. Thedisclosure of the above applications are incorporated herein byreference.

FIELD

The invention relates generally to a multiple speed transmission, andmore particularly, to a transmission having a plurality of speeds, threeor four planetary gear sets and a plurality of torque transmittingdevices.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may or may not constitute priorart.

A typical multiple speed transmission uses a combination of frictionclutches, planetary gear arrangements and fixed interconnections toachieve a plurality of gear ratios. The number and physical arrangementof the planetary gear sets, generally, are dictated by packaging, costand desired speed ratios.

While current transmissions achieve their intended purpose, the need fornew and improved transmission configurations which exhibit improvedperformance, especially from the standpoints of efficiency,responsiveness and smoothness, and improved packaging, primarily reducedsize and weight, is essentially constant. Accordingly, there is a needfor an improved, cost-effective, compact multiple speed transmission.

SUMMARY

A transmission for a motor vehicle is provided. The transmissionincludes an input member, an output member, a first planetary gear sethaving first, second, third, and fourth members, a second planetary gearset having first, second, and third members, a third planetary gear sethaving first, second, and third members, a first interconnecting memberdirectly connected to the second member of the first planetary gear setand to the second member of the second planetary gear set, a secondinterconnecting member directly connected to the first member of thesecond planetary gear set and the second member of the third planetarygear set, and six torque transmitting mechanisms selectively engageableto connect each of the first, second, third, and fourth members of thefirst, second, and third planetary gear sets with another of the first,second, third, and fourth members and a stationary member. The sixtorque transmitting mechanisms are engaged in combinations of at leastthree to provide at least ten forward speed ratios and a reverse speedratio between the input member and the output member.

In one aspect of the present invention, a first of the six torquetransmitting mechanisms is selectively engageable to connect the thirdmember of the first planetary gear set with the first member of thethird planetary gear set.

In another aspect of the present invention, a second of the six torquetransmitting mechanisms is selectively engageable to connect the thirdmember of the first planetary gear set with the third member of thethird planetary gear set.

In another aspect of the present invention, a third of the six torquetransmitting mechanisms is selectively engageable to connect the fourthmember of the first planetary gear set with the third member of thethird planetary gear set.

In another aspect of the present invention, a fourth of the six torquetransmitting mechanisms is selectively engageable to connect the thirdmember of the second planetary gear set with the third member of thethird planetary gear set.

In another aspect of the present invention, a fifth of the six torquetransmitting mechanisms is selectively engageable to connect the firstmember of the first planetary gear set to the stationary member.

In another aspect of the present invention, a sixth of the six torquetransmitting mechanisms is selectively engageable to connect the firstmember of the third planetary gear set to the stationary member.

In another aspect of the present invention, the input member isconnected for common rotation to the second member of the firstplanetary gear set and the second member of the second planetary gearset.

In another aspect of the present invention, the output member isconnected for common rotation to the first member of the secondplanetary gear set and the second member of the third planetary gearset.

In another aspect of the present invention, the first member of thefirst planetary gear set is a sun gear member, the second member of thefirst planetary gear set is a ring gear member, the third member of thefirst planetary gear set is a carrier member, the fourth member of thefirst planetary gear set is a ring and sun gear member, the firstmembers of the second and third planetary gear sets are ring gearmembers, the second members of the second and third planetary gear setsare carrier members, and the third members of the second and thirdplanetary gear sets are sun gear members.

In another aspect of the present invention, the first planetary gear setis a stacked planetary gear set having first and second sets ofplanetary gears supported for rotation by the carrier member, andwherein the first set of planetary gears is in mesh with the sun gearmember and the ring and sun gear member and the second set of planetarygears is in mesh with the ring and sun gear member and with the ringgear member.

In another aspect of the present invention, the first member of thefirst planetary gear set is a first sun gear member, the second memberof the first planetary gear set is a carrier member, the third member ofthe first planetary gear set is a ring gear member, the fourth member ofthe first planetary gear set is a second sun gear member, the firstmembers of the second and third planetary gear sets are ring gearmembers, the second members of the second and third planetary gear setsare carrier members, and the third members of the second and thirdplanetary gear sets are sun gear members.

In another aspect of the present invention, the first planetary gear setincludes a set of long planetary gears and a set of short planetarygears each supported by the carrier member, and wherein the longplanetary gears are each in mesh with the first sun gear member, thering gear member, and the short planetary gears, and wherein the shortplanetary gears are each in mesh with the long planetary gears and thesecond sun gear member.

In another aspect of the present invention, the first planetary gear setincludes a set of stepped planetary gears each having a large diameterportion and a small diameter portion and includes a set of non-steppedplanetary gears, wherein each of the stepped planetary gears are meshedwith the first sun gear member at the large diameter portion and areeach meshed with both the ring gear member and the non-stepped planetarygears at the small diameter portion, and wherein each of the non-steppedplanetary gears are meshed with both the stepped planetary gears and thesecond sun gear member.

In another aspect of the present invention, the first planetary gear setincludes a set of long planetary gears and a set of short planetarygears each supported by the carrier member, and wherein the longplanetary gears are each in mesh with the second sun gear member and theshort planetary gears, and wherein the short planetary gears are each inmesh with the long planetary gears, the first sun gear member, and thering gear member.

Further features, aspects and advantages of the present invention willbecome apparent by reference to the following description and appendeddrawings wherein like reference numbers refer to the same component,element or feature.

DRAWINGS

The drawings described herein are for illustration purposes only and arenot intended to limit the scope of the present disclosure in any way.

FIG. 1 is a lever diagram of a transmission according to the principlesof present invention;

FIG. 2 is a diagrammatic illustration of an embodiment of thetransmission of FIG. 1 according to the principles of the presentinvention;

FIG. 3 is a diagrammatic illustration of another embodiment of thetransmission of FIG. 1 according to the principles of the presentinvention;

FIG. 4 is a diagrammatic illustration of yet another embodiment of thetransmission of FIG. 1 according to the principles of the presentinvention;

FIG. 5 is a diagrammatic illustration of still another embodiment of thetransmission of FIG. 1 according to the principles of the presentinvention;

FIG. 6 is a diagrammatic illustration of yet another embodiment of thetransmission of FIG. 1 according to the principles of the presentinvention; and

FIG. 7 is a truth table presenting an example of a state of engagementof various torque transmitting elements to produce multiple forward andat least one reverse speed or gear ratios of the transmissionsillustrated in FIGS. 1-6.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is notintended to limit the present disclosure, application, or uses.

Referring now to FIG. 1, an embodiment of a multi-speed transmission 10is illustrated in a lever diagram format. A lever diagram is a schematicrepresentation of the components of a mechanical device such as anautomatic transmission. Each individual lever represents a planetarygear set wherein the three basic mechanical components of the planetarygear are each represented by a node. Therefore, a single lever containsthree nodes: one for the sun gear, one for the planet gear carrier, andone for the ring gear. In some cases, two levers may be combined into asingle lever having more than three nodes (typically four nodes). Forexample, if two nodes on two different levers are interconnected througha fixed connection they may be represented as a single node on a singlelever. The relative length between the nodes of each lever can be usedto represent the ring-to-sun ratio of each respective gear set. Theselever ratios, in turn, are used to vary the gear ratios of thetransmission in order to achieve an appropriate ratios and ratioprogression. Mechanical couplings or interconnections between the nodesof the various planetary gear sets are illustrated by thin, horizontallines, and torque transmitting devices such as clutches and brakes arepresented as interleaved fingers. Further explanation of the format,purpose and use of lever diagrams can be found in SAE Paper 810102, “TheLever Analogy: A New Tool in Transmission Analysis” by Benford andLeising which is hereby fully incorporated by reference.

The multi-speed transmission 10 includes an input shaft or member 12, afirst gear set assembly 14, a second gear set assembly 16, a third gearset assembly 18, and an output shaft or member 20. In the lever diagramof FIG. 1, the first gear set assembly 14 has four nodes: a first node14A, a second node 14B, a third node 14C, and a fourth node 14D. Thesecond gear set assembly 16 has three nodes: a first node 16A, a secondnode 16B and a third node 16C. The third gear set assembly 18 has threenodes: a first node 18A, a second node 18B and a third node 18C. Theinput member 12 is continuously coupled to the second node 14B of thefirst gear set assembly 14 and to the second node 16B of the second gearset assembly 16. The output member 20 is continuously coupled to thesecond node 18B of the third gear set assembly 18 and to the first node16A of the second gear set assembly 16.

A first clutch 22 selectively connects the third node 14C of the firstgear set assembly 14 with the first node 18A of the third gear setassembly 18. A second clutch 24 selectively connects the third node 14Cof the first gear set assembly 14 with the third node 18C of the thirdgear set assembly 18. A third clutch 26 selectively connects the fourthnode 14D of the first gear set assembly 14 with the third node 18C ofthe third gear set assembly 18. A fourth clutch 28 selectively connectsthe third node 16C of the second gear set assembly 16 with the thirdnode 18C of the third gear set assembly 18. A first brake 30 selectivelyconnects the first node 14A of the first gear set assembly 14 with astationary member or element 31, such as a transmission housing, inorder to restrict rotation of the first node 14A of the first gear setassembly 14. A second brake 32 selectively connects the first node 18Aof the third gear set assembly 18 with the stationary member 31 in orderto restrict rotation of the first node 18A of the third gear setassembly 18.

Referring now to FIG. 2, a stick diagram presents a schematic layout ofan embodiment of the multi-speed transmission 10 according to theprinciples of the present invention. In FIG. 2, the numbering from thelever diagram of FIG. 1 is carried over. The clutches and couplings arecorrespondingly presented whereas the nodes of the gear set assembliesnow appear as components of planetary gear sets such as sun gears, ringgears, planet gears and planet gear carriers.

For example, the first gear set assembly 14 is configured as a radiallystacked planetary gear set having a sun gear member 14A, a planet gearcarrier member 14C, a ring gear member 14B, and a sun/ring common gearmember 14D that are all radially aligned. The common gear member 14D hasgear teeth on an inner surface, forming a ring gear, and gear teeth onan outer surface, forming a sun gear. The carrier member 14C rotatablysupports a first set of planet or pinion gears 14E (only one of which isshown) and a second set of planet or pinion gears 14F (only one of whichis shown). The first set of planet gears 14E are each configured tointermesh with both the ring gear member 14B and the common gear member14D. The second set of planet gears 14F are each configured to intermeshwith both the common gear member 14D and the sun gear member 14A. Thesun gear member 14A is connected for common rotation with a first shaftor interconnecting member 34. The planet gear carrier 14C is connectedfor common rotation with a second shaft or interconnecting member 36.The common gear member 14D is connected for common rotation with a thirdshaft or interconnecting member 38. The ring gear 14B is connected forcommon rotation with the input shaft or member 12.

The second gear set assembly 16 includes a sun gear member 16C, a planetgear carrier member 16B, and a ring gear member 16A. The planet gearcarrier member 16B rotatably supports a set of planet or pinion gears16D (only one of which is shown). The planet gears 16D are eachconfigured to intermesh with both the sun gear member 16C and the ringgear member 16A. The sun gear member 16C is connected for commonrotation with a fourth shaft or interconnecting member 40. The carriermember 16B is connected for common rotation with the input shaft ormember 12. The ring gear member 16A is connected for common rotationwith the output shaft or member 20.

The third gear set assembly 18 includes a sun gear member 18C, a planetgear carrier member 18B, and a ring gear member 18A. The planet gearcarrier member 18B rotatably supports a set of planet or pinion gears18D (only one of which is shown). The planet gears 18D are eachconfigured to intermesh with both the sun gear member 18C and the ringgear member 18A. The sun gear member 18C is connected for commonrotation with a fifth shaft or interconnecting member 42. The carriermember 18B is connected for common rotation with the output shaft ormember 20. The ring gear member 18A is connected for common rotationwith a sixth shaft or interconnecting member 44.

The input shaft or member 12 is continuously connected to an inputsource, such as an engine (not shown) or a turbine of a torque converter(not shown). The output shaft or member 20 is continuously connectedwith a motor vehicle output such as a final drive unit or transfer case(not shown).

The torque-transmitting mechanisms, including the first, second, third,and fourth clutches 22, 24, 26, 28 and first and second brakes 30, 32allow for selective interconnection of the shafts or interconnectingmembers 34, 36, 38, 40, 42, 44 to other shafts or interconnectingmembers 34, 36, 38, 40, 42, 44, the members of the planetary gear sets14, 16, 18, or the stationary member or transmission housing 31. Forexample, the first clutch 22 is selectively engageable to connect thesecond interconnecting member 36 with the sixth interconnecting member44. The second clutch 24 is selectively engageable to connect the secondinterconnecting member 36 with the fifth interconnecting member 42. Thethird clutch 26 is selectively engageable to connect the thirdinterconnecting member 38 with the fifth interconnecting member 42. Thefourth clutch 28 is selectively engageable to connect the fourthinterconnecting member 40 with the fifth interconnecting member 42. Thefirst brake 30 is selectively engageable to connect the firstinterconnecting member 34 to the stationary member or transmissionhousing 31 in order to restrict the sun gear member 14A from rotatingrelative to the housing 31. The second brake 32 is selectivelyengageable to connect the sixth interconnecting member 44 to thestationary member or transmission housing 31 in order to restrictrotation of the ring gear member 18A.

Referring now to FIG. 3, a stick diagram presents a schematic layout ofanother embodiment of a multi-speed transmission 100 according to theprinciples of the present invention. In FIG. 3, the numbering from thediagrams of FIGS. 1 and 2 are carried over. The clutches and couplingsare correspondingly presented while the nodes of the gear set assemblies14, 16, and 18 may now correspond to different components of planetarygear sets from those illustrated in FIG. 2.

For example, the first gear set assembly 14 is configured as aRavigneaux planetary gear set having a first sun gear member 14A, asecond sun gear member 14D, a planet gear carrier member 14B, and a ringgear member 14C. The carrier member 14B rotatably supports a set of longplanet or pinion gears 14E (only one of which is shown) and a set ofshort planet or pinion gears 14F (only one of which is shown). The setof long planet gears 14E are each configured to intermesh with the ringgear member 14C, the sun gear member 14A and the short planet gears 14F.The short set of planet gears 14F are each configured to intermesh withboth the sun gear member 14D and the long planet gears 14E. The sun gearmember 14A is connected for common rotation with the first shaft orinterconnecting member 34. The ring gear member 14C is connected forcommon rotation with the second shaft or interconnecting member 36. Thesun gear member 14D is connected for common rotation with a third shaftor interconnecting member 38. The carrier member 14B is connected forcommon rotation with the input shaft or member 12.

The second gear set assembly 16 includes a sun gear member 16C, a planetgear carrier member 16B, and a ring gear member 16A. The planet gearcarrier member 16B rotatably supports a set of planet or pinion gears16D (only one of which is shown). The planet gears 16D are eachconfigured to intermesh with both the sun gear member 16C and the ringgear member 16A. The sun gear member 16C is connected for commonrotation with the fourth shaft or interconnecting member 40. The carriermember 16B is connected for common rotation with the input shaft ormember 12. The ring gear member 16A is connected for common rotationwith the output shaft or member 20.

The third gear set assembly 18 includes a sun gear member 18C, a planetgear carrier member 18B, and a ring gear member 18A. The planet gearcarrier member 18B rotatably supports a set of planet or pinion gears18D (only one of which is shown). The planet gears 18D are eachconfigured to intermesh with both the sun gear member 18C and the ringgear member 18A. The sun gear member 18C is connected for commonrotation with a fifth shaft or interconnecting member 42. The carriermember 18B is connected for common rotation with the output shaft ormember 20. The ring gear member 18A is connected for common rotationwith a sixth shaft or interconnecting member 44.

The input shaft or member 12 is continuously connected to an inputsource, such as an engine (not shown) or a turbine of a torque converter(not shown). The output shaft or member 20 is continuously connectedwith a motor vehicle output such as a final drive unit or transfer case(not shown).

The torque-transmitting mechanisms, including the first, second, third,and fourth clutches 22, 24, 26, 28 and first and second brakes 30, 32allow for selective interconnection of the shafts or interconnectingmembers 34, 36, 38, 40, 42, 44 to other shafts or interconnectingmembers 34, 36, 38, 40, 42, 44, the members of the planetary gear sets14, 16, 18, or the stationary member or transmission housing 31. Forexample, the first clutch 22 is selectively engageable to connect thesecond interconnecting member 36 with the sixth interconnecting member44. The second clutch 24 is selectively engageable to connect the secondinterconnecting member 36 with the fifth interconnecting member 42. Thethird clutch 26 is selectively engageable to connect the thirdinterconnecting member 38 with the fifth interconnecting member 42. Thefourth clutch 28 is selectively engageable to connect the fourthinterconnecting member 40 with the fifth interconnecting member 42. Thefirst brake 30 is selectively engageable to connect the firstinterconnecting member 34 to the stationary member or transmissionhousing 31 in order to restrict the sun gear member 14A from rotatingrelative to the housing 31. The second brake 32 is selectivelyengageable to connect the sixth interconnecting member 44 to thestationary member or transmission housing 31 in order to restrictrotation of the ring gear member 18A.

Referring now to FIG. 4, a stick diagram presents a schematic layout ofanother embodiment of a multi-speed transmission 200 according to theprinciples of the present invention. In FIG. 4, the numbering from thediagrams of FIGS. 1 and 3 are carried over. However, in the transmission200, the planet gears or pinions 14E are configured as stepped piniongears 201 having a larger diameter portion 202 and a small diameterportion 204. The large diameter portions 202 of each of the steppedplanet gears 201 are intermeshed with the sun gear member 14A. The smalldiameter portions 204 of each of the stepped planet gears 201 areintermeshed with both the ring gear member 14C and the planet gears 14F.The planet gears 14F are each intermeshed with both the stepped planetgears 201 and the sun gear member 14D.

Referring now to FIG. 5, a stick diagram presents a schematic layout ofanother embodiment of a multi-speed transmission 300 according to theprinciples of the present invention. In FIG. 5, the numbering from thediagrams of FIGS. 1 and 3 are carried over. However, in the transmission300, the long planet or pinion gears 14E are configured as short planetor pinion gears 302 and the short planet or pinion gears 14F areconfigured as long planet or pinion gears 304. The short planet gears302 are each intermeshed with both the sun gear member 14A, the ringgear member 14C, and the long planet gears 304. The long planet gears304 are each intermeshed with both the short planet gears 302 and thesun gear member 14D.

Referring now to FIG. 6, a stick diagram presents a schematic layout ofan embodiment of a multi-speed transmission 400 according to theprinciples of the present invention. In FIG. 6, the numbering from thelever diagram of FIG. 1 is carried over. The clutches and couplings arecorrespondingly presented whereas the nodes of the gear set assembliesnow appear as components of planetary gear sets such as sun gears, ringgears, planet gears and planet gear carriers.

For example, the first gear set assembly 14 is configured as twoseparate planetary gear sets including a first planetary gear set 402and a second planetary gear set 404. Therefore, some of the nodes of thefirst gear set assembly 14 represent multiple components of both thefirst and second planetary gear sets 402, 404. For example, the firstplanetary gear set 402 includes a sun gear member 402A, a planet gearcarrier member 402B, and a ring gear member 402C. The carrier member402B rotatably supports a set of planet or pinion gears 402D (only oneof which is shown). Each of the planet gears 402D are intermeshed withboth the sun gear member 402A and the ring gear member 402C. The secondplanetary gear set 404 includes a sun gear member 404A, a planet gearcarrier member 404B, and a ring gear member 404C. The carrier member404B rotatably supports a set of planet or pinion gears 404D (only oneof which is shown). Each of the planet gears 404D are intermeshed withboth the sun gear member 404A and the ring gear member 404C. Therefore,the first node 14A of the first gear set assembly 14 represents the sungear member 402A. The second node 14B of the first gear set assembly 14represents the carrier member 402B and the ring gear 404C. The thirdnode 14C of the first gear set assembly represents the ring gear member402C and the carrier member 404B. The fourth node 14D of the first gearset assembly 14 represents the sun gear member 404A.

The sun gear member 402A is connected for common rotation with a firstshaft or interconnecting member 434. The planet gear carrier 402B isconnected for common rotation with the input shaft or member 12. Thering gear member 402C is connected for common rotation with a secondshaft or interconnecting member 436.

The sun gear member 404A is connected for common rotation with a thirdshaft or interconnecting member 438. The carrier member 404B isconnected for common rotation with the second shaft or interconnectingmember 436. The ring gear member 404C is connected for common rotationwith the input shaft or member 12.

The second gear set assembly 16 includes a sun gear member 16C, a planetgear carrier member 16B, and a ring gear member 16A. The planet gearcarrier member 16B rotatably supports a set of planet or pinion gears16D (only one of which is shown). The planet gears 16D are eachconfigured to intermesh with both the sun gear member 16C and the ringgear member 16A. The sun gear member 16C is connected for commonrotation with a fourth shaft or interconnecting member 440. The carriermember 16B is connected for common rotation with the input shaft ormember 12. The ring gear member 16A is connected for common rotationwith the output shaft or member 20.

The third gear set assembly 18 includes a sun gear member 18C, a planetgear carrier member 18B, and a ring gear member 18A. The planet gearcarrier member 18B rotatably supports a set of planet or pinion gears18D (only one of which is shown). The planet gears 18D are eachconfigured to intermesh with both the sun gear member 18C and the ringgear member 18A. The sun gear member 18C is connected for commonrotation with a fifth shaft or interconnecting member 442. The carriermember 18B is connected for common rotation with the output shaft ormember 20. The ring gear member 18A is connected for common rotationwith a sixth shaft or interconnecting member 444.

The input shaft or member 12 is continuously connected to an inputsource, such as an engine (not shown) or a turbine of a torque converter(not shown). The output shaft or member 20 is continuously connectedwith a motor vehicle output such as a final drive unit or transfer case(not shown).

The torque-transmitting mechanisms, including the first, second, third,and fourth clutches 22, 24, 26, 28 and first and second brakes 30, 32allow for selective interconnection of the shafts or interconnectingmembers 434, 436, 438, 440, 442, 444 to other shafts or interconnectingmembers 434, 436, 438, 440, 442, 444, the members of the gear setassemblies 14, 16, 18, or the stationary member or transmission housing31. For example, the first clutch 22 is selectively engageable toconnect the second interconnecting member 436 with the sixthinterconnecting member 444. The second clutch 24 is selectivelyengageable to connect the second interconnecting member 436 with thefifth interconnecting member 442. The third clutch 26 is selectivelyengageable to connect the third interconnecting member 438 with thefifth interconnecting member 442. The fourth clutch 28 is selectivelyengageable to connect the fourth interconnecting member 440 with thefifth interconnecting member 442. The first brake 30 is selectivelyengageable to connect the first interconnecting member 434 to thestationary member or transmission housing 31 in order to restrict thesun gear member 402A from rotating relative to the housing 31. Thesecond brake 32 is selectively engageable to connect the sixthinterconnecting member 444 to the stationary member or transmissionhousing 31 in order to restrict rotation of the ring gear member 18A.

Referring now to FIG. 7 and with continued reference to FIGS. 2-6, theoperation of the multi-speed transmissions 10, 100, 200, 300, 400 willbe described. It will be appreciated that transmissions are capable oftransmitting torque from the input shaft or member 12 to the outputshaft or member 20 in multiple forward speed torque ratios and at leastone reverse speed or torque ratio. Each forward and reverse speed ortorque ratio is attained by engagement of one or more of thetorque-transmitting mechanisms (i.e. first brake 30, second brake 32,first clutch 22, second clutch 24, third clutch 26, and fourth clutch28), as will be explained below.

FIG. 7 is a truth table presenting the various combinations oftorque-transmitting mechanisms that are activated or engaged to achievethe various gear states. An “X” in the box means that the particularclutch or brake is engaged to achieve the desired gear state. Actualnumerical gear ratios of the various gear states are also presentedalthough it should be appreciated that these numerical values areexemplary only and that they may be adjusted over significant ranges toaccommodate various applications and operational criteria of thetransmissions. Of course, other gear ratios are achievable depending onthe gear diameter, gear teeth count and gear configuration selected.

For example, a reverse gear is established by engaging or activating thesecond brake 32, the third clutch 26, and the first clutch 22. Likewise,the ten forward speed or gear ratios are achieved through differentcombinations of clutch and brake engagement, as shown in FIG. 7, by wayof example. FIG. 7 also illustrates multiple clutch and brake engagementoptions for achieving fourth gear and seventh gear.

It should be appreciated that the shafts or interconnecting members 12,20, 34, 36, 38, 40, 42, 44, 434, 436, 438, 440, 442, and 444 may each besingle unitary members or each may be comprised of multipleinterconnected rotatable members without departing from the scope of thepresent invention.

The description of the invention is merely exemplary in nature andvariations that do not depart from the gist of the invention areintended to be within the scope of the invention. Such variations arenot to be regarded as a departure from the spirit and scope of theinvention.

The following is claimed:
 1. A transmission for a motor vehiclecomprising: an input member; an output member; a first planetary gearset having a first sun gear, a second sun gear, a carrier member, and aring gear; a second planetary gear set having a sun gear, a carriermember, and a ring gear; a third planetary gear set having a sun gear, acarrier member, and a ring gear; a first interconnecting member directlyconnected to the carrier member of the first planetary gear set and tothe carrier member of the second planetary gear set; a secondinterconnecting member directly connected to the ring gear of the secondplanetary gear set and the carrier member of the third planetary gearset; and six torque transmitting mechanisms each selectively engageableto connect one of the sun gears, carrier members, and rings gears withanother of the sun gears, carrier members, rings gears and a stationarymember, and wherein the six torque transmitting mechanisms are engagedin combinations of at least three to provide at least ten forward gearratios and at least one reverse gear ratio between the input member andthe output member.
 2. The transmission of claim 1 wherein a first of thesix torque transmitting mechanisms is selectively engageable to connectthe ring gear of the first planetary gear set with the ring gear of thethird planetary gear set.
 3. The transmission of claim 1 wherein asecond of the six torque transmitting mechanisms is selectivelyengageable to connect the ring gear of the first planetary gear set withthe sun gear of the third planetary gear set.
 4. The transmission ofclaim 1 wherein a third of the six torque transmitting mechanisms isselectively engageable to connect the second sun gear of the firstplanetary gear set with the sun gear of the third planetary gear set. 5.The transmission of claim 1 wherein a fourth of the six torquetransmitting mechanisms is selectively engageable to connect the sungear of the second planetary gear set with the sun gear of the thirdplanetary gear set.
 6. The transmission of claim 1 wherein a fifth ofthe six torque transmitting mechanisms is selectively engageable toconnect the first sun gear of the first planetary gear set to thestationary member.
 7. The transmission of claim 1 wherein a sixth of thesix torque transmitting mechanisms is selectively engageable to connectthe ring gear of the third planetary gear set to the stationary member.8. The transmission of claim 1 wherein the input member is connected forcommon rotation to the carrier member of the first planetary gear setand the carrier member of the second planetary gear set via the firstinterconnecting member.
 9. The transmission of claim 1 wherein theoutput member is connected for common rotation to the ring gear of thesecond planetary gear set and the carrier member of the third planetarygear set.
 10. The transmission of claim 1 wherein the first planetarygear set includes a set of long planetary gears and a set of shortplanetary gears each supported by the carrier member, and wherein thelong planetary gears are each in mesh with the first sun gear, the ringgear, and the short planetary gears, and wherein the short planetarygears are each in mesh with the long planetary gears and the second sungear.
 11. The transmission of claim 1 wherein the first planetary gearset includes a set of stepped planetary gears each having a largediameter portion and a small diameter portion and includes a set ofnon-stepped planetary gears, wherein each of the stepped planetary gearsare meshed with the first sun gear at the large diameter portion and areeach meshed with both the ring gear and the non-stepped planetary gearsat the small diameter portion, and wherein each of the non-steppedplanetary gears are meshed with both the stepped planetary gears and thesecond sun gear.
 12. The transmission of claim 1 wherein the firstplanetary gear set includes a set of long planetary gears and a set ofshort planetary gears each supported by the carrier member, and whereinthe long planetary gears are each in mesh with the second sun gear andthe short planetary gears, and wherein the short planetary gears areeach in mesh with the long planetary gears, the first sun gear, and thering gear.
 13. A transmission for a motor vehicle comprising: an inputmember; an output member; a first planetary gear set having a first sungear, a second sun gear, a carrier member, and a ring gear; a secondplanetary gear set having a sun gear, a carrier member, and a ring gear;a third planetary gear set having a sun gear, a carrier member, and aring gear; a first torque transmitting mechanism selectively engageableto connect the ring gear of the first planetary gear set with the ringgear of the third planetary gear set; a second torque transmittingmechanism selectively engageable to connect the ring gear of the firstplanetary gear set with the sun gear of the third planetary gear set; athird torque transmitting mechanism selectively engageable to connectthe second sun gear of the first planetary gear set with the sun gear ofthe third planetary gear set; a fourth torque transmitting mechanismselectively engageable to connect the sun gear of the second planetarygear set with the sun gear of the third planetary gear set; a fifthtorque transmitting mechanism selectively engageable to connect thefirst sun gear of the first planetary gear set to the stationary member;a sixth torque transmitting mechanism selectively engageable to connectthe ring gear of the third planetary gear set to the stationary member,and wherein the six torque transmitting mechanisms are engaged incombinations of at least three to provide at least ten forward gearratios and at least one reverse gear ratio between the input member andthe output member.
 14. The transmission of claim 13 further comprising afirst interconnecting member directly connected to the carrier member ofthe first planetary gear set and to the carrier member of the secondplanetary gear set.
 15. The transmission of claim 13 further comprisinga second interconnecting member directly connected to the ring gear ofthe second planetary gear set and the carrier member of the thirdplanetary gear set.
 16. The transmission of claim 13 wherein the inputmember is connected for common rotation to the carrier member of thefirst planetary gear set and the carrier member of the second planetarygear set via the first interconnecting member.
 17. The transmission ofclaim 13 wherein the output member is connected for common rotation tothe ring gear of the second planetary gear set and the carrier member ofthe third planetary gear set.
 18. The transmission of claim 13 whereinthe first planetary gear set includes a set of long planetary gears anda set of short planetary gears each supported by the carrier member, andwherein the long planetary gears are each in mesh with the first sungear, the ring gear, and the short planetary gears, and wherein theshort planetary gears are each in mesh with the long planetary gears andthe second sun gear.
 19. The transmission of claim 13 wherein the firstplanetary gear set includes a set of stepped planetary gears each havinga large diameter portion and a small diameter portion and includes a setof non-stepped planetary gears, wherein each of the stepped planetarygears are meshed with the first sun gear at the large diameter portionand are each meshed with both the ring gear and the non-steppedplanetary gears at the small diameter portion, and wherein each of thenon-stepped planetary gears are meshed with both the stepped planetarygears and the second sun gear.
 20. The transmission of claim 13 whereinthe first planetary gear set includes a set of long planetary gears anda set of short planetary gears each supported by the carrier member, andwherein the long planetary gears are each in mesh with the second sungear and the short planetary gears, and wherein the short planetarygears are each in mesh with the long planetary gears, the first sungear, and the ring gear.